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    68 Products

    Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknuts.
    Versatile yet economical, these are the most commonly used locknuts. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Black-Corrosion-Resistant-Coated Steel—These nuts combine a finished appearance with the rust resistance of stainless steel. The coating has been tested to extreme standards, including 1,000 hours of salt spray resistance, to hold up in wet and outdoor environments. Also known as black luster.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    10-32
    		3/8"15/64"22010000000000000000
     
    Black-Corrosion-Resistant-Coated Steel
    10-32
    		3/8"15/64"22050000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They resist rust in wet and outdoor environments, but won't hold up to the harsh chemicals that 316 stainless steel can.
    316 Stainless Steel—Our most corrosion-resistant nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"15/64"22010000000000000000
     
    Black-Oxide 18-8 Stainless Steel
    10-32
    		3/8"15/64"2202500000000000000
     
    316 Stainless Steel
    10-32
    		3/8"15/64"220500000000000000
     
    High-Strength Lightweight Titanium
    Grade 5 Titanium—The best of both worlds, these locknuts are lightweight like aluminum and as corrosion-resistant as 316 stainless steel. They're ideal for use in chemical-processing and water-treatment facilities since they stand up to strong acids and other harsh chemicals. Grade 5 is the strongest of all the titanium alloys due to its higher aluminum and vanadium content.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp.
    Pkg.
    Qty.
    Pkg.
    Grade 5 Titanium
    10-32
    		3/8"15/64"Not Rated100000000000000
     
    Lightweight Aluminum
    6061 Aluminum—One-third the weight of steel, these nuts are commonly used in robotics, automation, and other applications that have weight limitations. They're an alternative to stainless steel for rust resistance but are not as strong.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    6061 Aluminum
    10-32
    		3/8"15/64"2202500000000000000
     
    Brass
    Brass—Conductive and nonmagnetic, brass locknuts are typically used to secure electrical equipment, such as circuit board assemblies and mounting brackets inside enclosures. They're also softer than most metals, so they won't damage other fastening components.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Brass
    10-32
    		3/8"15/64"2202500000000000000
     

    Thin-Profile Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Thin-Profile Nylon-Insert Locknuts.
    About half the height of standard-profile locknuts, these fit in spaces with low clearance. You can also use them as jam nuts by threading them against a hex nut to hold it in place. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Black-Zinc-Plated Steel—The dark zinc plating withstands occasional exposure to moisture while creating a finished look.
    Black-Corrosion-Resistant-Coated Steel—These nuts combine a finished appearance with the rust resistance of stainless steel. The coating has been tested to extreme standards, including 1,000 hours of salt spray resistance, to hold up in wet and outdoor environments. Also known as black luster.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    10-32
    		3/8"11/64"22010000000000000000
     
    Black-Zinc-Plated Steel
    10-32
    		3/8"11/64"220250000000000000
     
    Black-Corrosion-Resistant-Coated Steel
    10-32
    		3/8"11/64"22050000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They resist rust in wet and outdoor environments, but won't hold up to the harsh chemicals that 316 stainless steel can.
    316 Stainless Steel—Our most corrosion-resistant nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"11/64"2205000000000000000
     
    Black-Oxide 18-8 Stainless Steel
    10-32
    		3/8"3/16"22010000000000000000
     
    316 Stainless Steel
    10-32
    		3/8"11/64"2205000000000000000
     

    Mil. Spec. Distorted-Thread Flange Nuts

    Not only do these have the strongest hold of all the flange nuts we offer, they are also manufactured and tested to strict U.S. military standards for material and construction. They have irregularly shaped threads that grip the screw to resist loosening in high-vibration applications. The threads prevent the nut from backing out, but they also increase the effort to install and remove. To get these nuts off, you may need special tools, such as an impact wrench or propane torch, so they are not reusable. Nuts have a flange that distributes pressure evenly across the mounting surface without the need for a separate washer. They are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. Also known as collar nuts.
    Low-Strength Steel
    Image of Product. Front orientation. Flange Nuts. Mil. Spec. Distorted-Thread Flange Nuts.
    About half the strength of medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Cadmium-Plated Steel—The plating reduces friction during installation, so these nuts thread on smoother than others. It also creates a barrier against rust that's comparable to zinc yellow-chromate plating.
    Cadmium Yellow-Chromate-Plated Steel—Better corrosion resistance than plain cadmium. These nuts withstand salt water and are suitable for most wet and outdoor environments.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Mil.
    Spec.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    10-32
    		1/4"3/16"0.33"0.03"MS21042L3500000000000000
     
    Cadmium Yellow-Chromate-Plated Steel
    10-32
    		1/4"3/16"0.33"0.03"MS21042-350000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Flange Nuts. Mil. Spec. Distorted-Thread Flange Nuts.
    High-Temperature A286 Stainless Steel—Stronger than 316 stainless steel and withstand high temperatures up to 1500° F. These nuts resist corrosion from chemicals, such as bleach and chlorine, but they won't hold up to salt water as well as 316 stainless steel.
    High-Temperature Silver-Plated A286 Stainless Steel—The silver plating reduces friction during installation, so these nuts thread on smoother than others. They are stronger than 316 stainless steel and withstand temperatures up to 800° F. Nuts resist corrosion from chemicals, such as bleach and chlorine, but won't hold up to salt water as well as 316 stainless steel.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Mil.
    Spec.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    High-Temperature A286 Stainless Steel
    10-32
    		1/4"3/16"0.33"0.02"—NAS1291C3M100000000000000
     
    High-Temperature Silver-Plated A286 Stainless Steel
    10-32
    		1/4"3/16"0.33"0.03"MS21043-3—500000000000000
     

    Serrated Flange Nuts

    Image of Product. Bottom orientation. Flange Nuts. Serrated Flange Nuts.
    Serrations bite into material for mild vibration resistance while the flange eliminates the need for a separate washer. These nuts are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. You can use them again and again without sacrificing strength. However, the serrations may mar the surface of your material. Also known as collar nuts.
    Low-Strength Steel
    About half the strength of medium-strength steel nuts, these are suitable for light duty fastening applications, such as securing access panels. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating that creates a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    Zinc-Flake-Coated Steel—The most durable zinc coating, zinc flake is a multilayer finish that resists wear for long-term rust protection. Similar to zinc yellow-chromate, it won't hold up to harsh chemicals like stainless steel can.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    10-32
    		3/8"7/32"1/2"0.03"10000000000000000
     
    Black-Oxide Steel
    10-32
    		3/8"7/32"1/2"0.03"1000000000000000
     
    Zinc-Flake-Coated Steel
    10-32
    		3/8"7/32"1/2"0.03"250000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Highly Corrosion-Resistant 316 Stainless Steel—Our most corrosion-resistant flange nuts, these hold up in just about any environment, including harsh weather, salt water, and most chemicals.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"7/32"1/2"0.09"5000000000000000
     
    Highly Corrosion-Resistant 316 Stainless Steel
    10-32
    		3/8"7/32"1/2"0.03"2500000000000000
     

    Locknuts with External-Tooth Lock Washer

    Image of Product. Front orientation. ZoomedIn view. Locknuts. Locknuts with External-Tooth Lock Washer.
    To save on assembly time, these locknuts combine a hex nut with a free-spinning lock washer, so you can twist them into place by hand. Once the nut is against your material surface, tighten it down with a wrench or socket to get the teeth to bite. Although these nuts install more quickly than nylon-insert locknuts, they don't hold up as well against vibration and can mar your material. As long as the washer stays intact, you can reuse them. Also known as Keps and K-lock nuts.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Black-Zinc-Plated Steel—The dark zinc plating withstands occasional exposure to moisture while creating a finished look.
    Thread
    Size
    Wd.
    Ht.
    Washer
    OD
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    10-32
    		3/8"5/32"0.406"10000000000000000
     
    Black-Zinc-Plated Steel
    10-32
    		3/8"5/32"0.406"1000000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Washer
    OD
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"11/64"0.406"100000000000000000
     

    Nylon-Insert Flange Nuts

    A nylon insert grips the screw for a stronger hold than a serrated flange, without damaging threads or marring the surface of your material. However, the insert may become brittle if exposed to high temperatures. These nuts have a flange that distributes pressure evenly across the mounting surface, so you don't need a separate washer. They are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. You can reuse them a handful of times, but their holding power will decrease with each use. Also known as collar nuts.
    Medium-Strength Steel
    Image of Product. Front orientation. Flange Nuts. Nylon-Insert Flange Nuts.
    Rated Grade 5, Grade F, or Class 8, these nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating that creates a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    10-32
    		3/8"17/64"0.5"0.03"ASME Grade F
    		25010000000000000000
     
    Black-Oxide Steel
    10-32
    		3/8"17/64"0.49"0.04"ASME Grade F
    		25010000000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Flange Nuts. Nylon-Insert Flange Nuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They resist rust in wet and outdoor environments, but won't hold up to the harsh chemicals that 316 stainless steel can.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"9/32"0.49"0.07"250500000000000000
     
    Black-Oxide 18-8 Stainless Steel
    10-32
    		3/8"9/32"0.49"0.07"25050000000000000
     

    Mil. Spec. Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Mil. Spec. Nylon-Insert Locknuts.
    These locknuts are manufactured and tested to strict U.S. military standards for material and construction. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Cadmium Yellow-Chromate-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    10-32
    		3/8"9/32"MS21044-N32501000000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"9/32"MS21044C3250NASM2104410000000000000000
     

    Nylon-Insert Locknut Assortments

    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknut Assortments.
    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknut Assortments.
    With a range of sizes on hand, you can use these assortments to fasten a variety of parts. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    No. of
    Pieces
    Locknuts Included
    Container
    Type
    Each
    Zinc-Plated Steel
    5504-40 (100 Pieces)
    6-32 (100 Pieces)
    8-32 (100 Pieces)
    10-24 (100 Pieces)
    10-32 (100 Pieces)
    1/4"-20 (50 Pieces)    		Plastic Box000000000000000
     
    18-8 Stainless Steel
    5504-40 (100 Pieces)
    6-32 (100 Pieces)
    8-32 (100 Pieces)
    10-24 (100 Pieces)
    10-32 (100 Pieces)
    1/4"-20 (50 Pieces)    		Plastic Box00000000000000
     

    Mil. Spec. Thin-Profile Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Mil. Spec. Thin-Profile Nylon-Insert Locknuts.
    These locknuts are manufactured and tested to strict U.S. military standards for material and construction. They are about half the height of standard-profile locknuts to fit in spaces with low clearance. You can also use them as jam nuts by threading them against a hex nut to hold it in place. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Cadmium Yellow-Chromate-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    10-32
    		3/8"3/16"MS21083N3250NASM210831000000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"3/16"MS21083C3250NASM210835000000000000000
     

    Top-Lock Distorted-Thread Locknuts

    Image of Product. Front orientation. Locknuts. Top-Lock Distorted-Thread Locknuts.
    Irregularly shaped threads at the top of these locknuts grip the screw for a stronger hold than nylon-insert locknuts. Although the threads prevent the nut from backing out due to vibration, they also increase the effort to install and remove. To get these nuts off, you may need special tools, such as an impact wrench or propane torch. Nuts are not reusable.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    10-32
    		3/8"1/8"SAE Grade 2
    		100000000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    316 Stainless Steel—Our most corrosion-resistant nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"1/8"5000000000000000
     
    316 Stainless Steel
    10-32
    		3/8"1/8"100000000000000
     

    Thread-Forming Locknuts

    Image of Product. Bottom orientation. Locknuts. Thread-Forming Locknuts.
    Form threads into these nuts for a tight fit that won't loosen under vibration. They are partially threaded, so when you fasten them onto metal screws, the tightening action will cut the rest of the threads. Nuts are not reusable.
    Plastic
    Nylon 6/6—Slippery and abrasion resistant, these nuts thread on smoothly and stand up to daily wear and tear. Nylon will swell and weaken when exposed to moisture, so it's best for dry environments.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    White Nylon 6/6
    10-32
    		23/64"9/64"100000000000000000
     

    Mil. Spec. Flex-Top Locknuts for Heavy Vibration

    Image of Product. Front orientation. Locknuts. Mil. Spec. Flex-Top Locknuts for Heavy Vibration.
    These locknuts are manufactured and tested to strict U.S. military standards for material and construction. The top section expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. As a result, they're suitable for use in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Steel
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    10-32
    		3/8"1/4"MS21045-3500000000000000
     
    Corrosion-Resistant Stainless Steel
    Silver-Plated 18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts won't rust. The silver plating adds lubricity to help them thread on smoothly during installation.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Silver-Plated 18-8 Stainless Steel
    10-32
    		3/8"15/64"MS21046C3NASM210461000000000000000
     

    Flex-Top Locknuts for Heavy Vibration

    Image of Product. Front orientation. Locknuts. Flex-Top Locknuts for Heavy Vibration.
    The top section of these nuts expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. They’re often used in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Steel
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    10-32
    		3/8"1/4"25000000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They resist rust in wet and outdoor environments, but won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"1/4"10000000000000000
     
    Black-Oxide 18-8 Stainless Steel
    10-32
    		3/8"1/4"50000000000000
     

    Thin-Profile Flex-Top Locknuts for Heavy Vibration

    Image of Product. Front orientation. Locknuts. Thin-Profile Flex-Top Locknuts for Heavy Vibration.
    About two-thirds the height of standard flex-top nuts, these fit in spaces with low clearance. You can also use them as jam nuts by threading them against a hex nut to hold it in place. The top section expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. As a result, they're suitable for use in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Steel
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    10-32
    		3/8"3/16"25000000000000000
     
    Steel
    10-32
    		3/8"3/16"100000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"3/16"10000000000000000
     

    Locknuts with Spring-Lock Washer

    Image of Product. Front orientation. Locknuts. Locknuts with Spring-Lock Washer.
    The curved, spring-like washer grips surfaces more tightly than tooth-lock washers for better vibration resistance. These locknuts also install just as quickly since you can twist them into place by hand. Once the nut is against your material, tighten it down with a wrench or socket. The washer's smooth edges won't mar the surface like teeth can. As long as the washer stays intact, you can reuse these locknuts.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    Thread
    Size
    Wd.
    Ht.
    Washer
    OD
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    10-32
    		3/8"3/16"0.406"25000000000000000
     
    Black-Oxide Steel
    10-32
    		3/8"3/16"0.406"100000000000000
     

    Locknuts for use with Cotter Pins

    Image of ProductInUse. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    Image of Product. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    Use these locknuts to secure rotating parts subjected to mild vibration, such as the wheels on carts and hand trucks. They’re not recommended for use on parts exposed to high vibration because the pin can shear under prolonged stress. These nuts are reusable, but you'll need a new cotter pin (not included) with each use.
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    For Cotter
    Pin Dia.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"1/4"3/64"500000000000000
     

    Cap Nuts with Threadlocker

    Image of Product. Front orientation. Contains Annotated, Border. Cap Nuts. Cap Nuts with Threadlocker.
    These nuts not only conceal and protect protruding screw threads, they also resist loosening from mild vibration. They have a nylon patch bonded to their threads that grips screws for a tighter hold than standard cap nuts. They’re reusable a handful of times, but the patch’s holding power decreases with each use. Also known as acorn nuts, they have a smooth, rounded head that creates a finished look.
    Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these nuts have a dark, matte coating. They resist rust in wet and outdoor environments but won't hold up to the harsh chemicals that 316 stainless steel can.
    Highly Corrosion-Resistant 316 Stainless Steel—Our most corrosion-resistant cap nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/16"3/8"13/32"5000000000000000
     
    Black-Oxide 18-8 Stainless Steel
    10-32
    		3/16"3/8"13/32"500000000000000
     
    Highly Corrosion-Resistant 316 Stainless Steel
    10-32
    		3/16"3/8"13/32"500000000000000
     

    Nylon-Insert Wing Nuts

    Image of Product. Front orientation. Thumb Nuts. Nylon-Insert Wing Nuts.
    The strongest hold of all our thumb nuts. The wings give you extra leverage for a tight fit, while a nylon insert grips the screw to prevent loosening from vibration. However, the insert may become brittle if exposed to high temperatures. You can reuse these nuts a handful of times, but their holding power will decrease with each use.
    Zinc
    Zinc—Zinc nuts have better corrosion resistance than steel to withstand occasional exposure to moisture. However, they're not as strong.
    Thread
    Size
    Wd.
    Ht.
    Base
    Dia.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc
    10-32
    		1 1/32"1/2"3/8"22525000000000000000
     

    Nylon-Insert Cap Nuts

    Image of Product. Bottom orientation. Cap Nuts. Nylon-Insert Cap Nuts.
    Get the protection of a cap nut with the vibration resistance of a locknut. These nuts not only conceal protruding screw threads, they also have a nylon insert that grips the screw to prevent loosening from moderate vibration. However, the insert may become brittle if exposed to high temperatures. Nuts are reusable a handful of times, but their holding power decreases with each use.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these nuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Nylon 6/6 Cap—The nylon cap on these nuts is softer than metal, so it's less likely to scratch surrounding surfaces or parts.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel with Nylon 6/6 Cap
    10-32
    		9/64"3/8"23/64"SAE Grade 2
    		2502500000000000000
     
    Steel with Nylon 6/6 Cap
    10-32
    		9/64"3/8"23/64"SAE Grade 2
    		250250000000000000
     

    Distorted-Thread Flange Nuts

    Image of Product. Bottom orientation. Flange Nuts. Distorted-Thread Flange Nuts.
    The strongest hold of all the flange nuts we offer, these have irregularly shaped threads that grip the screw to resist loosening. The threads prevent the nut from backing out due to high vibration, but they also increase the effort to install and remove. To get these nuts off, you may need special tools, such as an impact wrench or propane torch, so they are not reusable. Nuts have a flange that distributes pressure evenly across the mounting surface without the need for a separate washer. They are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. Also known as collar nuts.
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/8"7/32"0.5"0.03"500000000000000
     

    Serrated Locknuts

    Image of Product. Front orientation. Locknuts. Serrated Locknuts.
    Since these nuts twist on by hand and don't require much torque, they're the easiest locknuts to install. The serrated edge grips surfaces to secure equipment that experiences mild vibration, such as panel covers and small electric motors. You can reuse these locknuts over and over again, but the serrations may mar your surface.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    10-32
    		3/8"1/8"50000000000000000
     

    Assortments of Locknuts with External-Tooth Lock Washer

    Image of Product. Front orientation. Locknuts. Assortments of Locknuts with External-Tooth Lock Washer.
    Image of Product. Front orientation. ZoomedIn view. Locknuts. Assortments of Locknuts with External-Tooth Lock Washer.
    With a range of sizes on hand, you can use these assortments to fasten a variety of parts. These locknuts combine a hex nut with a free-spinning lock washer, so you can twist them into place by hand and save on assembly time. Once the nut is against your material surface, tighten it down with a wrench or socket to get the teeth to bite. Although these nuts install more quickly than nylon-insert locknuts, they don't hold up as well against vibration and can mar your material. As long as the washer stays intact, you can reuse them. Also known as Keps and K-lock nuts.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    No. of
    Pieces
    Locknuts Included
    Container
    Type
    Each
    Zinc-Plated Steel
    6004-40 (100 Pieces)
    6-32 (100 Pieces)
    8-32 (100 Pieces)
    10-24 (100 Pieces)
    10-32 (100 Pieces)
    1/4"-20 (100 Pieces)    		Plastic Box000000000000000
     
    18-8 Stainless Steel
    6004-40 (100 Pieces)
    6-32 (100 Pieces)
    8-32 (100 Pieces)
    10-24 (100 Pieces)
    10-32 (100 Pieces)
    1/4"-20 (100 Pieces)    		Plastic Box00000000000000
     

    Press-Fit Locknuts for Sheet Metal

    Image of Product. Bottom orientation. Press-Fit Nuts. Press-Fit Locknuts for Sheet Metal.
    Image of Product. Bottom orientation. Press-Fit Nuts. Press-Fit Locknuts for Sheet Metal.
    The nylon insert inside these nuts grips screws so they won't back out or loosen. Use them to keep thin parts fastened on engines and other vibrating machinery.
    Cadmium Yellow-Chromate-Plated Steel—Thread fasteners on these nuts smoothly without sticking. The plating also creates a stronger barrier against rust than zinc.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust and mild chemicals.
    Thread
    Size
    Drill Bit
    Size
    For Min.
    Panel Thk.
    For Maximum Panel
    Hardness
    Head
    Ht.
    Flange
    Dia.
    Pkg.
    Qty.
    Pkg.
    Nylon-Insert Locking
     
    Cadmium Yellow-Chromate-Plated Steel
    10-32
    		1/4"
    		0.05"Brinell 205, Rockwell B950.18"0.34"10000000000000000
     
    18-8 Stainless Steel
    10-32
    		1/4"
    		0.05"Brinell 190, Rockwell B900.18"0.34"1000000000000000
     

    Distorted-Thread Cap Nuts

    Image of Product. Bottom orientation. Cap Nuts. Distorted-Thread Cap Nuts.
    For a stronger hold than nylon-insert cap nuts, these have irregularly shaped threads that grip the screw to resist loosening. The threads prevent the nut from backing out in high-vibration applications, but they also increase the effort to install and remove. To get these nuts off, you may need special tools, such as an impact wrench or propane torch. They have a smooth, rounded head that conceals and protects protruding screw threads while creating a finished look. Nuts are not reusable.
    Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Highly Corrosion-Resistant 316 Stainless Steel—Our most corrosion-resistant cap nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    		3/16"3/8"13/32"10000000000000000
     
    Highly Corrosion-Resistant 316 Stainless Steel
    10-32
    		3/16"3/8"13/32"10000000000000
     
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these nuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    10-32
    		3/16"3/8"13/32"SAE Grade 2
    		25000000000000000
     

    Self-Aligning Press-Fit Locknuts for Sheet Metal

    Image of Product. Front orientation. Press-Fit Nuts. Self-Aligning Press-Fit Locknuts for Sheet Metal.
    Image of Product. Front orientation. Press-Fit Nuts. Self-Aligning Press-Fit Locknuts for Sheet Metal.
    Fasten together unaligned parts and keep screws in place. The threaded hole within these press-fit nuts shifts up to .01" in any direction, so you can fasten together thin panels with off-center holes. The irregularly shaped threads tightly grip screws to prevent them from loosening or backing out under vibration.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust and mild chemicals.
    Head
    Barrel
    Thread
    Size
    Drill Bit
    Size
    For Min.
    Panel Thk.
    For Maximum Panel
    Hardness
    OD
    Ht.
    Dia.
    Ht.
    PEM® Part
    No.
    Pkg.
    Qty.
    Pkg.
    Distorted-Thread Locking
     
    18-8 Stainless Steel
    10-32
    		13/32"
    		0.038"Brinell 125, Rockwell B700.47"0.038"7/32"17/64"LAC-032-1MD5000000000000000
    10-32
    		13/32"
    		0.054"Brinell 125, Rockwell B700.47"0.054"17/64"17/64"LAC-032-2MD500000000000000
     
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